This invention relates to the secure latching of a component to a substrate and particularly, but not exclusively, concerns the secure latching of an electrical connector, for example, a pin header, to a substrate. Especially where solder tails projecting from a component are to be soldered to conductors on the substrate, the component should be immovably fixed to the substrate so that cracking of the solder joints and backing out of the solder tails are avoided.
U.S. Pat. Nos. 5,085,589, 5,104,339 and 5,145,407 disclose metal latches which are secured to the housing of a pin header connector, or the like, and which are configured to lock into a hole in a substrate.
There is disclosed in U.S. Pat. No. 5,085,589, a latch having a pair of latching legs each having a barb presenting a lip which latches beneath the underside of a substrate in parallel relationship therewith. Since the latching legs are coplanar with each other, the length of the lips is necessarily restricted in relation to the diameter of the hole in the substrate, because the flexure of the latching legs, as they are inserted into the hole, is restricted by abutment between the latching legs. In order to stabilize the connector on the substrate, a third latching leg may be provided in offset relationship with the pair of latching legs and having a detent which is engageable beneath the substrate. There is also disclosed, a latch having several latching legs distributed in circular array and each having an inclined cam surface which engages against the bottom corner of the hole.
U.S. Pat. No. 5,104,339 discloses a latch made of wire and having a pair of latching legs which are deformed into crossed relationship by insertion through a restricted passage in connector housing, by means of an arm of a machine, for example, a robot. The passage is aligned with a hole in a substrate and the machine arm forces the crossed latching legs through the hole, whereafter the latching legs resile so that inclined shoulders on the latching legs engage against the bottom corner of the hole in the substrate.
There is disclosed in U.S. Pat. No. 5,145,407 a latch having a pair of legs which are offset from each other so that they cross as they are inserted through a hole in a substrate so that bevels on the legs engage against the side of the hole.